Poor adherence to continuous positive airway pressure (CPAP) treatment remains the single largest impediment to effective management for obstructive sleep apnea (OSA). While successful interventions to improve CPAP adherence may ultimately include a variety of components, for patients living with spouses (refers to all domestic partners) the spouse will likely be integral to any successful intervention. However, we know very little about the characteristics and impact of spousal involvement on CPAP adherence. Thus, this R15 project will examine the role of spousal involvement in adherence to CPAP, with the long-term goal of developing a couple-based intervention to promote CPAP use. Two aims are directed toward developing understanding of the nature of spousal involvement in CPAP adherence. Aims: Aim 1 addresses the impact of spousal involvement on CPAP adherence and will attempt to isolate the types of spousal support that are beneficial versus types that are detrimental. One hundred and thirty-three (133) couples (CPAP nave OSA patients and their spouses) will be followed for 3 months after CPAP treatment initiation. Because greater daily CPAP use optimizes clinical benefits, CPAP adherence in this study will be primarily assessed as average daily use at 3-months and at 1-week. Couple's dyadic coping and patient affective response to spousal involvement will also be examined. Aim 2 focuses on developing an in-depth understanding of the couple's experiences with CPAP therapy, how the couples cope with CPAP, and the facilitators and barriers to incorporating CPAP into daily life. In-person open-ended interviews will be conducted with 20-25 couples, including OSA patients with various levels of CPAP adherence and their spouses to obtain a wide range of participant perspectives. Significance / Innovation: This study will expand the conceptual context of CPAP adherence from an exclusive focus on individual patients to a broader dyadic perspective for both patients and their spouses. Innovative methodological approaches are used to understand the nature of spousal involvement in CPAP adherence, such as recruiting the couple as a unit and dyadic evaluation from both partners. While known to be effective in addressing other conditions, the use of social support programs engaging spouses is untested in OSA. Next Steps: This project will provide data that will allow us to better understand the role of spousal involvement in CPAP adherence, and serves to inform the development of an effective and sustainable intervention that will improve CPAP adherence.